NEW YORK, NY - JUNE 21: J.R. Martinez attends the "The Shallows" world premiere at AMC Loews Lincoln Square on June 21, 2016 in New York City. (Photo by Dimitrios Kambouris/Getty Images)
(2016 Getty Images)

Earlier this week, Republican presidential nominee Donald Trump joked that he “always wanted” a Purple Heart and that it was “much easier” to receive one from a supporter than to earn the military decoration.

His comments did not sit well with U.S. Army veteran, motivational speaker and "Dancing with the Stars" winner J.R. Martinez, who wrote an open letter to Trump asking him to stop disrespecting veterans and the country’s fallen heroes.

“I am a proud post-9/11 U.S. Army veteran and Purple Heart recipient,” he wrote in the letter published Wednesday on Mic.com. “When I first joined the military, like many other service members, I had dreams of serving valiantly and one day receiving many military accolades in service of our great nation.”

He continued: “I can tell you without equivocation that the one award I did not want to receive was a Purple Heart, but I got one anyway. And I'll tell you now, I didn't get mine the easy way.”

Martinez, 33, was serving in Iraq in 2003 when a Humvee hit a roadside bomb, burning more than 34 percent of his body. He has undergone 34 surgeries since his injury.

“I came home with a Purple Heart recipient, but my mother knew that we were only a few heartbeats away from giving her a new designation — a Gold Star,” he wrote.

His open letter also comes days after Trump took to Twitter and fanned the flames of yet another potentially damaging political feud: his flap with Khizr and Ghazala Khan, a Muslim-American family whose son, Capt. Humayun Khan, was killed while serving in Iraq in 2004.

Khzir Khan took the stage at least week's Democratic National Convention to accuse Trump of sacrificing "nothing and no one." Trump, famous for never letting a slight go, hit back in an interview over the weekend — including by implying that soldier's mother stood silently alongside her husband during the speech because her religion restricted her from speaking — and then returned to it on social media to start the week.

"Mr. Khan, who does not know me, viciously attacked me from the stage of the DNC and is now all over T.V. doing the same - Nice!" he posted.

Mr. Khan, who does not know me, viciously attacked me from the stage of the DNC and is now all over T.V. doing the same - Nice!

The back-and-forth between the nominee and the Khans soon escalated, prompting several top Republicans and The Veterans of Foreign Wars, a nonprofit service organization with 1.7 million members, to denounce Trump.

“So far you seem to have denigrated a prisoner of war, disparaged a four-star general who devoted his life to service, and disrespected the faith and the grief of a Gold Star family,” Martinez told Trump in his letter. “Any one of these actions alone would otherwise disqualify a person auditioning for the role of our commander in chief.”

He continued: “You say that you support our military, but your actions tell a different story.”

Speaking specifically about the Khans, Martinez said: “If your response to this family had simply been to acknowledge their ultimate sacrifice and to say that as Americans they are constitutionally entitled to their opinions, that would have been enough. You chose a different tactic. You chose to stay in the news cycle with your increasingly outrageous statements of condemnation of a family who, by all accounts, should absolutely be off limits.”

Martinez then wrote that the memory of “our fallen soldiers, their families, former POWs, and the proud recipients of the Purple Heart honor” is off-limits.

“These are the people who will defend you. These are their families you are talking about. These are not the people you want to continue to carry out your petty grievances and personal attacks with,” he said.